Jan. I, 1894.] THE TROPICAL AGRICULTURIST. 
447 
CEYLON MANUAL OF CHEMI- 
CAL ANALYSES. 
A HANDBOOK OF ANALYSES CONNECTED WITH THE 
INDUSTRIES AND PUBLIC HEALTH OF CEYLON FOR 
PLANTERS, COMMERCIAL MEN, AGRICULTURAL 
STUDENTS, AND MEMBERS OF LOCAL BOARDS. 
By M. COCHRAN, m.a., f.c.s. 
(Continued from page 31 o. J 
CHAPTER. IX. 
MANURES. 
Principles of manuring— nitrogen and r.un- 
fall— phosphoric acid— potash— lime— clas- 
sification of manures ceylon cattle 
manure- ceylon cattle dung— farmyard 
manure— compost manures— manures of 
commerce— nitrogenous manures— ammo- 
nium sulphate — sodium nitrate— soot — 
dried flesh— dried blood— woollen refuse 
and hair— crushed oilcakes — fresh and 
old castor-cakes— potash in castor-cakes 
—analyses of various samples of castor- 
cakes— coconut poonac— crushed tallow 
oil cake— phosphoric acid manures— bone- 
ash animal charcoal mineral phos- 
phates phosphatic guanos superphos- 
phates precipitated phosphates— basic 
slau-potash manures-german potash salts 
—kainit—carnallite— plant-ashes— wood- 
ashes of the kumbuk tree— ashes of marine 
plants— mixed seaweeds— coimmercial sul- 
phate of potash— volcanic ashes— nitroge- 
nous and phosphatic manures— crushed 
bones— bone dust as used in ceylon- refuse 
bone dust — degelatinized bone meal— fish 
manure— guanos— peruvian — equalised pe- 
ruvian— ichaboe— meat guano— nitroge- 
nous superphosphates — vitriolated and 
dissolved bones— nitrogenaus and potas- 
sic manures— nitrate of potash— phos- 
phoric acid and potash manures— mixture 
of white castor cake bone-meal and 
nitre— mountain limestone— ground coral 
. — magnesian limestone or dolomite — 
' estate made lime -gas lime— colombo gas 
lime— common salt— composition of sea- 
salt — european rock salts— sulphate of 
iron— commercial fertilisers for coffee, 
tea, and tobacco — valuation of manures 
—table of values in colombo. 
Man urea. 
Manures ai'e laubHtances which are added to th® 
soil to increase or to maintain its fertility. 
Manures may accomplish this in two ways ; 
tir.st, V)y the direct acldition of plant food to the 
soil ; second, by rendering available the elements 
of plant food already in the soil. 
In the art of manuring the agriculturist has to 
take special account of these fonr constituents 
of plant food, viz : — nitrogen, phosphoric acid, 
potash, and lime ; as these, but more especially 
the first three, are the constituents of plants in 
which the soil is likelj' to be deficient. 
Nitrogen. 
Nitrogen is an element of tiio greatest im- 
portance to the fertility of the soil. There is, 
of course, an abundant supply of nitrogen in 
our atmos])here, in the unconibined state ; but 
this is directly availal)lc as the food of plants 
to a very limited e.\teiit. Tlie ([ucatiou how far 
it is available i^ oae .which has, of late, much 
51 
occupied the minds of scientists, and has been 
the subject of many practical experiments. 
At present the opinion is that most plants are 
unable to assimilate to any appreciable degree 
the free nitrogen of the atnio.sphere ; but that 
plants of the natural order leguminosae possess 
to a marked extent the power through the 
intervention of microbes, of assimilating the 
free nitrogen of the atmosphere. The assimi- 
lation takes place in microbe-bearintr nodule.s 
or tubercles, which are developed on"the roots 
of the leguminosae. 
Although the free nitrogen of the atmosphere 
cannot be counted upon as a direct source 
of plant food for other than leguminous plants, 
the atmosphere contains a small proportion of 
nitrogen in the forms of ammonia and nitric acid 
which is brought down to the earth by the 
rains, and which constitutes an important part 
of the food of plants. 
By the systematic analysis of rain water 
throughout the year, in various parts of the 
worlds calculations have been made of the amount 
of nitrogen carried into the soil in the forms of 
ammonia and nitric acid. Mr. R. Warrington, 
F.RS., determined the amount of nitrogen in a 
year's rainfall at Rothamstead,* St. Albans, from 
May 1888 to 1889. He found that the amount of 
nitrogen present as ammonia varied from -238 
parts per million in the month of February, to 
1-025 parts per million in the month of September, 
and the proportion for the whole year was -426 
parts per million eijual to 2-823 lbs. per acre. 
The nitrogen as nitrates and nitrites varied 
from -09.3 parts per million in February to -253 
in September, the average for the whole year 
being -139 parts per million equal to -917 lbs. 
per acre. The total nitrogen present as ammonia 
and as nitric and nitrous acids is thus 3-74 lbs. 
per acre. 
Much higher figures than these have been 
obtained in Germany, and in Italy the average 
at 7 agricultural stations representing the 
rainfall of thirteen years, being 1-26 parts per 
million of nitrogen as ammonia and •■47 parts 
per million of nitrogen as nitric acid, or a 
total of lO'lS lbs. of nitrogen per acre per annum. 
At the Observatory of Mont Souris, Paris, the 
average of ten years showed 1'82 parts per million 
of nitrogen as ammonia, and -70 of nitrogen as 
nitric acid equal to 12-36 lbs. of nitrogen per acre 
per annum. 
On the other hand, results obtained from 
Lincoln, New Zealand, and from Tokio, Japan, 
are below the Rotliamstead figures. Professor 
Gravy found in the former country, in an average 
of three years' rainfall -096 parts per million of 
ammoniacal nitrogen and -15 of nitric nitrogen 
equal to a total of 1-6 lbs. of nitrogen per acre 
per annum. 
At Tokio, Kellner found in one year's rainfall 
■]26 parts per million of ammoniacal nitrogen 
equal to 1-78 lbs. per acre, and in another year's 
rainfall -085 parts per million of nitric nitrogen 
equal to 1-02 lbs. per acre, showing thus a total 
of 2-8 lbs. of nitrogen per acre per annum. 
We are not yet in a position to make similar 
calculations for any part of Ceylon, as no .such 
systematic analyses of rain water liave been 
made throughout the year, and isolated analyses 
• Messrs. Lawes and Gilbert found that the 
amount of nitrogen furnished annually in tho rain- 
fall to an acre of land at Rothamstead aiuounttd 
to 7"21 lbs., of which O-lc lbs. occurred as ammonia 
and -75 lbs. in the form gf nitli« acic|.— fit'^i."' ^"'i". 
(anju'cot. •■* *■ " 
